1910.] AND TDK .Mll.l ITl'HKUCl'LATA. 7().") 



In Cynorlonts the pulate is relatively iiaiTow and never iierfoiiited. 

 It seems probable that as mastication became established and 

 the palate became greatly widened perforation would be likely to 

 occur. It is still found in most Marsupials, but it is also met 

 with in Eutherians, e. g. Erinaceas and Macroscelides. 6. " There 

 appears to bean alisphenoid can^d and a well-developed alisphenoid 

 bulla." It is admitted that this region is crushed and broken, 

 and that the chaiucters cannot be made out clearly. So far as 

 the figure shows, the condition is veiy unlike that seen in Mar- 

 supials, and the structure of the back of the jaw confirms this. 

 In neither Ptilodus nor Plngiaulax is thei'e an}- distinct angle, 

 and in Ctenacodon. the angle is very small. This is quite luilike 

 what is seen in Marsupials, where both in the Diprotodonts and 

 the Polyprotodonts a well-developed angle curves round a large 

 alisphenoid bulla. 7. "There is a distinct*' notch on the inferior 

 inner border of the [occipital] condyle, a character also observed 

 in some of the living diprotodont Marsupials." The exact shape 

 of the occipital condyle dej)ends much on the habits of the animal, 

 and most of the marsupial peculiaiities seem to be paralleled by 

 some of the higher forms. If we knew the arrangement of the 

 for-amina for the ix^A, x//i, xiiA, and especially xii^A nerves, we 

 would have a point of more value in settling the affinities than 

 anything else connected with the skull. The lower jaw is mar- 

 supial in having the lower posteiior portion inflected, but in the 

 practical absence of a distinct angle it diflei's considerably. 



The humerus, it is stated, " is distinctly eutherian throughout, 

 and is very uidike that of any of the living Monotremes." Though 

 in general shape it is very unlike the humerus of either Echidna 

 or Ornithorhynchihs and bears a superficial resemblance to that of 

 Marsupials and Eutherians, the lower end is quite unlike anything 

 known in any living mammal, and certainly very diflt'erent from 

 the ordinary marsupial type. In fact, the aiticular portion comes 

 nearer to the monotreme type than to that of any of the higher 

 forms. 



The pelvis is too imperfect to throw much light on the affinities. 



The femur and tibia so far as preserved are certainly not 

 marsupial in type, being very unlike those of either Diprotodonts 

 or Polyprotodonts*. 



Doubtless all the bones both of the skull and limbs are super- 

 ficially more like those of Marsupials than Monotremes. but one 

 is too apt to forget that the only living Monotremas are de- 

 generate dwarfed digging animals, and are probably much worse 

 types of the Prototheria than Tcdpa and Chrysochloris are of 

 the Eutheria. 



Taking all the points into consideiution, we find that there is 

 nothing in the postcranial skeleton that is distinctly marsupial, 



* The unequal development of the fore and hind limbs is a point of no weight 

 in determining affinities. The condition in Macrnpns is probably a ver^' recent 

 modification. A similar developmenfis met with in liopping anima's otv<trious 

 orders, e.g. Jfacrosceliden. Fedetes, &c. 



Pnoc! Zooi.. 800.-1910, No. L. .")0 



